Five years ago, today, four suicide bombers blew themselves up while riding on London’s subway system and on one of its famous, red, double-decker buses. The devastating result was 52 murdered and some 800 injured.

For a city and a nation that had dealt with Irish terrorism for more than a hundred years, the attacks on July 7, 2005 were nevertheless a shock. This threat was of a new order. Not only were these terrorists hoping to kill civilians in massive numbers and willing to die in the effort but they—unlike the Irish terrorists—had an agenda that could not be addressed through political means and some reasonable set of compromises.

No less chilling was the fact that MI-5, Britain’s domestic intelligence service, had few clues suggesting the four were planning the operation. This was not principally a case, as many argued in the wake of the attacks on 9/11, of various security agencies not sharing relevant information. None of the four were on MI-5’s list of some 800 “primary” investigative targets.

Indeed, Mohammad Sidique Khan, the group’s ring leader, had never openly espoused radical jihadist views and was a second-generation British citizen. Security conscious, Khan could, and did, operate below Scotland Yard and MI-5’s radar.

None of this is surprising. Throughout the 1990s, London, in particular, became a safe haven for many of the world’s most vocal and active Islamic extremists. Dubbed “Londonistan” by critics of the British government’s lax attitude toward Islamic radicalism, the problem was doubly complicated by the fact that tens of thousands of British residents were making extended trips back to visit relatives in Central and South Asia. Keeping track of the potentially dangerous few who might use the occasion to be schooled in the terrorist arts was a task a then under-manned and under-resourced British intelligence effort could not fulfill.

The U.K. already had laws to deal with terrorism, including surveillance powers that were far more intrusive than anything comparable in the United States and “control orders” which allowed the government to put suspects under virtual “house arrest” indefinitely.

But after the 7/7 bombings, the government supplemented those laws by adding resources to MI-5 and the Metropolitan Police, creating new institutional arrangements to facilitate closer cooperation between the police and intelligence units, and giving the police new authorities. Among the new powers were allowing the police to detain a terrorist suspect for up to four weeks without a charge being brought and by making it a crime to encourage terrorism or disseminate terrorist publications.

On the one hand, the effort to bolster the British government’s counterterrorism capabilities has worked. Since July 2005, more than 700 terrorism suspects have been arrested in the UK and the country has not suffered a major terrorism attack. This is not because Islamist-inspired jihadists have not been trying.

Virtually every year, a significant plot has been disrupted or failed for lack of sophistication because of police and intelligence success in disrupting existing terrorist support systems. In 2008 and 2009 alone, there were 90 Islamist-related terrorism verdicts handed down by the UK courts.

However, as the numbers above suggest, the terrorist threat has not gone away. The threat level today stands at “severe,” meaning that the government believes a terrorist attack is “highly likely” sometime in the near future. With more than 2,000 individuals in the UK identified today by police and the security service as posing a terrorist threat and needing fairly constant monitoring, the job has not gotten any easier.

Despite this, and perhaps somewhat predictably given the success in preventing a second 9/11 or 7/7, there is on-going debate in Britain about amending, or doing away with altogether, some of the counterterrorism authorities that have been put on the books since 2005. There is also the new Tory-Liberal government’s proposal to slash police funding by twenty-five percent.

For many in the U.K., this is simply a matter of readjusting the balance between security and liberty that arose in the wake of terrorist attacks that struck New York, Madrid and then London. While it was to be expected that tougher measures would be implemented following those attacks, it’s also to be expected that a democracy will review the steps taken in light of lessons learned and experience gained.

For others in the U.K., however, the cuts and the possible changes in the laws are playing with fire. With an overstretched security service, a threat that remains substantial and the Summer Olympics’ impending arrival in London in 2012, the question being asked is whether these changes are truly wise. Undoubtedly, some balance between civil liberties and security is required.

But securing the life and limb of one’s citizens is a fundamental duty of liberal, democratic states as well. And, the fact is, in carrying out that charge in the face of remarkably virulent domestic threat, the U.K. remains one of the most free and decent places in which to live in the world.

Gary Schmitt is director of advanced strategic studies at the American Enterprise Institute and the contributing editor to the forthcoming AEI volume, "Safety, Liberty and Islamist Terrorism: American and European Approaches to Domestic Counterterrorism."

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